An inverter generally comprises a chopper circuit having pairs in chopper transistors that are connected to each other in series. These pairs of chopper transistors are connected in parallel between a first line and to a second line. The first line is at a power supply potential and the second line is at ground potential. Such inverters are subjected to thermal stresses and they are subjected to surge voltages and to fast variations in voltage that stress their components.
In order to remedy those drawbacks, it is known to associate a chopper circuit with a snubber circuit that comprises a capacitive element and a charging diode for charging the capacitive element, which capacitive element and charging diode are connected to each other in series and together they are connected in parallel with one of the chopper transistors in each pair of chopper transistors. The snubber circuit also includes a resistor having a first end connected to a connection point situated between the charging diode and the capacitive element, and a second end connected to the first line. Thus, when the chopper transistor switches from its conductive stage to its non-conductive state, the energy loss resulting from switching is recovered via the diode in the capacitive element that enables a zero voltage to be maintained across the terminals of the transistor. When the chopper transistor is controlled to switch to its conductive state, the energy stored in the capacitive element is dissipated in the resistor. A chopper circuit fitted with such a snubber circuit thus presents poor efficiency.